Revert "Revert "Revert "Revert "Add implicit null and stack checks for x86""""
This reverts commit 0025a86411145eb7cd4971f9234fc21c7b4aced1.
Bug: 16256184
Change-Id: Ie0760a0c293aa3b62e2885398a8c512b7a946a73
diff --git a/compiler/dex/quick/x86/call_x86.cc b/compiler/dex/quick/x86/call_x86.cc
index b7441d7..40dd9cc 100644
--- a/compiler/dex/quick/x86/call_x86.cc
+++ b/compiler/dex/quick/x86/call_x86.cc
@@ -222,15 +222,28 @@
LockTemp(rs_rX86_ARG1);
LockTemp(rs_rX86_ARG2);
- /* Build frame, return address already on stack */
- stack_decrement_ = OpRegImm(kOpSub, rs_rX86_SP, frame_size_ - GetInstructionSetPointerSize(cu_->instruction_set));
-
/*
* We can safely skip the stack overflow check if we're
* a leaf *and* our frame size < fudge factor.
*/
- const bool skip_overflow_check = mir_graph_->MethodIsLeaf() &&
- !IsLargeFrame(frame_size_, cu_->target64 ? kX86_64 : kX86);
+ InstructionSet isa = cu_->target64 ? kX86_64 : kX86;
+ const bool skip_overflow_check = mir_graph_->MethodIsLeaf() && !IsLargeFrame(frame_size_, isa);
+
+ // If we doing an implicit stack overflow check, perform the load immediately
+ // before the stack pointer is decremented and anything is saved.
+ if (!skip_overflow_check &&
+ cu_->compiler_driver->GetCompilerOptions().GetImplicitStackOverflowChecks()) {
+ // Implicit stack overflow check.
+ // test eax,[esp + -overflow]
+ int overflow = GetStackOverflowReservedBytes(isa);
+ NewLIR3(kX86Test32RM, rs_rAX.GetReg(), rs_rX86_SP.GetReg(), -overflow);
+ MarkPossibleStackOverflowException();
+ }
+
+ /* Build frame, return address already on stack */
+ stack_decrement_ = OpRegImm(kOpSub, rs_rX86_SP, frame_size_ -
+ GetInstructionSetPointerSize(cu_->instruction_set));
+
NewLIR0(kPseudoMethodEntry);
/* Spill core callee saves */
SpillCoreRegs();
@@ -260,25 +273,27 @@
private:
const size_t sp_displace_;
};
- // TODO: for large frames we should do something like:
- // spill ebp
- // lea ebp, [esp + frame_size]
- // cmp ebp, fs:[stack_end_]
- // jcc stack_overflow_exception
- // mov esp, ebp
- // in case a signal comes in that's not using an alternate signal stack and the large frame may
- // have moved us outside of the reserved area at the end of the stack.
- // cmp rs_rX86_SP, fs:[stack_end_]; jcc throw_slowpath
- if (cu_->target64) {
- OpRegThreadMem(kOpCmp, rs_rX86_SP, Thread::StackEndOffset<8>());
- } else {
- OpRegThreadMem(kOpCmp, rs_rX86_SP, Thread::StackEndOffset<4>());
- }
- LIR* branch = OpCondBranch(kCondUlt, nullptr);
- AddSlowPath(
+ if (!cu_->compiler_driver->GetCompilerOptions().GetImplicitStackOverflowChecks()) {
+ // TODO: for large frames we should do something like:
+ // spill ebp
+ // lea ebp, [esp + frame_size]
+ // cmp ebp, fs:[stack_end_]
+ // jcc stack_overflow_exception
+ // mov esp, ebp
+ // in case a signal comes in that's not using an alternate signal stack and the large frame
+ // may have moved us outside of the reserved area at the end of the stack.
+ // cmp rs_rX86_SP, fs:[stack_end_]; jcc throw_slowpath
+ if (cu_->target64) {
+ OpRegThreadMem(kOpCmp, rs_rX86_SP, Thread::StackEndOffset<8>());
+ } else {
+ OpRegThreadMem(kOpCmp, rs_rX86_SP, Thread::StackEndOffset<4>());
+ }
+ LIR* branch = OpCondBranch(kCondUlt, nullptr);
+ AddSlowPath(
new(arena_)StackOverflowSlowPath(this, branch,
frame_size_ -
GetInstructionSetPointerSize(cu_->instruction_set)));
+ }
}
FlushIns(ArgLocs, rl_method);
@@ -318,4 +333,14 @@
NewLIR0(kX86Ret);
}
+void X86Mir2Lir::GenImplicitNullCheck(RegStorage reg, int opt_flags) {
+ if (!(cu_->disable_opt & (1 << kNullCheckElimination)) && (opt_flags & MIR_IGNORE_NULL_CHECK)) {
+ return;
+ }
+ // Implicit null pointer check.
+ // test eax,[arg1+0]
+ NewLIR3(kX86Test32RM, rs_rAX.GetReg(), reg.GetReg(), 0);
+ MarkPossibleNullPointerException(opt_flags);
+}
+
} // namespace art